DEVICE FOR MEASURING CONCENTRATION OF CONSTITUENT IN BLOOD ANDMEASURING METHOD

• US 20090270701A1
• Filed: 04/23/2009
• Published: 10/29/2009
• Est. Priority Date: 04/25/2008
• Status: Active Grant

• Current Assignee: DENSO Corporation, Nippon Soken, Inc.
• Original Assignee: DENSO Corporation, Nippon Soken, Inc.
• Inventors: HASEO, Yasuyuki, NISHII, Katsuyoshi, TATSUMOTO, Hirohiko, OSAKI, Rie, KOMURA, Takashi
• Granted Patent: US 8,655,426 B2
• Time in Patent Office: Days
• US Class Current: 600/316
• CPC Class Codes: A61B 2562/146 for optical coupling
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes

Abstract

A device for measuring concentration of a constituent in blood includes: an irradiation unit for irradiating light toward a living body, the light having a wavelength disposed in a light absorption band of the constituent in the blood; a light receiving unit for receiving light, which is reflected in the living body or transmitted through the living body; and a concentration measurement unit for measuring the concentration of the constituent in the blood based on variation of light intensity of light received by the light receiving unit, the variation attributed to a pulse wave of the living body.

Claims

1. A device for measuring concentration of a constituent in blood comprising:

an irradiation unit for irradiating light toward a living body, the light having a wavelength disposed in a light absorption band of the constituent in the blood;

a light receiving unit for receiving light, which is reflected in the living body or transmitted through the living body; and

a concentration measurement unit for measuring the concentration of the constituent in the blood based on variation of light intensity of light received by the light receiving unit, the variation attributed to a pulse wave of the living body.

2. The device according to claim 1,

wherein the concentration measurement unit measures the concentration of the constituent in the blood based on variation of a wave height of light intensity attributed to the pulse wave of the living body.

3. The device according to claim 2,

wherein the concentration measurement unit measures the concentration of the constituent in the blood based on a comparison between the wave height of light intensity and a predetermined reference wave height.

4. The device according to claim 3, further comprising:

a memory for storing a standard curve between a wave height ratio and the concentration of the constituent in blood,

wherein the concentration measurement unit calculates the wave height ratio between the wave height of light intensity and the predetermined reference wave height, and

wherein the concentration measurement unit measures the concentration of the constituent in the blood based on the wave height ratio and the standard curve.

5. The device according to claim 2,

wherein the irradiation unit is capable of irradiating a plurality of types of light having different wavelengths,

wherein the light receiving unit is capable of receiving the plurality of types of light,

wherein the concentration measurement unit calculates the wave height of light intensity in each type of light, and

wherein the concentration measurement unit measures the concentration of the constituent in the blood based on a comparison between the wave heights in different types of light.

6. The device according to claim 5,

wherein the plurality of types of light includes a first light having a first wavelength and a second light having a second wavelength,

wherein concentration measurement unit calculates a first wave height of light intensity in the first light, and calculates a second wave height of light intensity in the second light,

wherein the concentration measurement unit calculates a ratio between the first and second wave heights, and

wherein the concentration measurement unit measures the concentration of the constituent in the blood based on a comparison between the ratio and a predetermined reference ratio.

7. The device according to claim 6, further comprising:

a memory for storing a standard curve between the ratio and the concentration of the constituent in blood,

wherein the concentration measurement unit measures the concentration of the constituent in the blood based on the ratio and the standard curve.

8. The device according to claim 1,

wherein the irradiation unit irradiates light toward a fingertip of the living body.

9. The device according to claim 1, further comprising:

a holding unit for maintaining a contact pressure of the irradiation unit to be constant, the irradiation unit press-contacting the living body.

10. The device according to claim 1,

wherein the constituent in blood is alcohol, glucose, glycogen, protein or cholesterol.

11. A method for measuring concentration of a constituent in blood comprising:

irradiating light toward a living body, the light having a wavelength disposed in a light absorption band of the constituent in the blood;

receiving light reflected in the living body or transmitted through the living body; and

measuring the concentration of the constituent in the blood based on variation of light intensity of received light, the variation attributed to a pulse wave of the living body.

12. The method according to claim 11,

wherein the concentration of the constituent in the blood is measured based on variation of a wave height of light intensity attributed to the pulse wave of the living body.

13. The method according to claim 12,

wherein the concentration of the constituent in the blood is measured based on a comparison between the wave height of light intensity and a predetermined reference wave height.

14. The method according to claim 12,

wherein the irradiating light includes irradiating a plurality of types of light having different wavelengths, the method further comprising:

calculating the wave height of light intensity in each type of light among plurality of types of light,

wherein the concentration of the constituent in the blood is measured based on a comparison between the wave heights in different types of light.

15. The method according to claim 11,

wherein the light is irradiated toward a fingertip of the living body.

16. The method according to claim 11,

wherein the constituent in blood is alcohol, glucose, glycogen, protein or cholesterol.